Consequences of intrauterine growth restriction on ventilatory and thermoregulatory responses to asphyxia and hypercapnia in the newborn guinea-pig

2002 ◽  
Vol 14 (2) ◽  
pp. 85 ◽  
Author(s):  
Mary Tolcos ◽  
Sandra Rees ◽  
Hugh McGregor ◽  
David Walker
Keyword(s):  
Steady State ◽  
Guinea Pig ◽  
Intrauterine Growth Restriction ◽  
Minute Ventilation ◽  
Immunohistochemical Analysis ◽  
Growth Restriction ◽  
Ventilatory Responses ◽  
Prenatal Growth ◽  
Thermoregulatory Responses ◽  
And Control

The purpose of this study was to determine the effects of prenatal growth restriction on the ventilatory and thermoregulatory responses to asphyxia and hypercapnia in the newborn guinea-pig. Spontaneously growth-restricted (SGR) animals born to unoperated dams, and growth-retarded (GR) neonates born to dams in which a uterine artery had been ligated at mid gestation, were studied and compared with control neonates. Ventilatory responses to progressive asphyxia and steady-state hypercapnia were tested at 3–6 days of age using a barometric plethysmograph. The animals were then killed and the brains prepared for histological and immunohistochemical analysis. During progressive asphyxia, SGR neonates (n = 5) had a significantly increased minute ventilation compared with both control (n = 6) and GR (n = 5) neonates. Rectal temperature fell significantly in GR and SGR neonates after progressive asphyxia, but was unchanged in control neonates. The ventilatory responses to steady-state hypercapnia were not different in the GR, SGR and control neonates. The immunoreactive expression of glial fibrillary acidic protein, tyrosine hydroxylase, substance P and met-enkephalin in the medulla was also not different between the three groups. It was concluded that prenatal growth restriction is associated with alterations in the respiratory and thermoregulatory responses to asphyxia and hypercapnia, with greater effects observed when in utero growth restriction arises spontaneously, compared with that produced experimentally over approximately the last half of gestation.

Effects of airway anesthesia on ventilatory responses to graded dead spaces and CO2

1988 ◽  
Vol 64 (5) ◽  
pp. 1885-1892 ◽  
Author(s):  
C. Shindoh ◽  
W. Hida ◽  
Y. Kikuchi ◽  
T. Chonan ◽  
H. Inoue ◽  
...  
Keyword(s):  
Steady State ◽  
Dead Space ◽  
Ventilatory Response ◽  
Minute Ventilation ◽  
Co2 Response ◽  
Co2 Gas ◽  
Ventilatory Responses ◽  
Before And After ◽  
End Tidal ◽  
And Control

Ventilatory response to graded external dead space (0.5, 1.0, 2.0, and 2.5 liters) with hyperoxia and CO2 steady-state inhalation (3, 5, 7, and 8% CO2 in O2) was studied before and after 4% lidocaine aerosol inhalation in nine healthy males. The mean ventilatory response (delta VE/delta PETCO2, where VE is minute ventilation and PETCO2 is end-tidal PCO2) to graded dead space before airway anesthesia was 10.2 +/- 4.6 (SD) l.min-1.Torr-1, which was significantly greater than the steady-state CO2 response (1.4 +/- 0.6 l.min-1.Torr-1, P less than 0.001). Dead-space loading produced greater oscillation in airway PCO2 than did CO2 gas loading. After airway anesthesia, ventilatory response to graded dead space decreased significantly, to 2.1 +/- 0.6 l.min-1.Torr-1 (P less than 0.01) but was still greater than that to CO2. The response to CO2 did not significantly differ (1.3 +/- 0.5 l.min-1.Torr-1). Tidal volume, mean inspiratory flow, respiratory frequency, inspiratory time, and expiratory time during dead-space breathing were also depressed after airway anesthesia, particularly during large dead-space loading. On the other hand, during CO2 inhalation, these respiratory variables did not significantly differ before and after airway anesthesia. These results suggest that in conscious humans vagal airway receptors play a role in the ventilatory response to graded dead space and control of the breathing pattern during dead-space loading by detecting the oscillation in airway PCO2. These receptors do not appear to contribute to the ventilatory response to inhaled CO2.

scholarly journals Prenatal intrauterine growth restriction and risk of retinopathy of prematurity

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Alison Chu ◽  
Yasmeen Dhindsa ◽  
Myung Shin Sim ◽  
Marie Altendahl ◽  
Irena Tsui
Keyword(s):  
Gestational Age ◽  
Retinopathy Of Prematurity ◽  
Intrauterine Growth Restriction ◽  
Growth Failure ◽  
Postnatal Growth ◽  
Growth Patterns ◽  
Growth Restriction ◽  
Intrauterine Growth ◽  
Prenatal Growth ◽  
Postnatal Growth Failure

Abstract Low birthweight and decreased postnatal weight gain are known predictors of worse retinopathy of prematurity (ROP) but the role of prenatal growth patterns in ROP remains inconclusive. To distinguish small for gestational age (SGA) from intrauterine growth restriction (IUGR) as independent predictors of ROP, we performed a retrospective cohort study of patients who received ROP screening examinations at a level IV neonatal intensive care unit over a 7-year period. Data on IUGR and SGA status, worst stage of and need for treatment for ROP, and postnatal growth was obtained. 343 infants were included for analysis (mean gestational age = 28.6 weeks and birth weight = 1138.2 g). IUGR infants were more likely to have a worse stage of ROP and treatment-requiring ROP (both p < 0.0001) compared to non-IUGR infants. IUGR infants were more likely to be older at worst stage of ROP (p < 0.0001) and to develop postnatal growth failure (p = 0.01) than non-IUGR infants. Independent of postnatal growth failure status, IUGR infants had a 4–5 × increased risk of needing ROP treatment (p < 0.001) compared to non-IUGR infants. SGA versus appropriate for gestational age infants did not demonstrate differences in retinopathy outcomes, age at worst ROP stage, or postnatal growth failure. These findings emphasize the importance of prenatal growth on ROP development.

scholarly journals The weight gain influence of pregnant women under different clinical conditions on weight at the birth of newborns.

2020 ◽  
Author(s):  
Márcia Dornelles Machado Mariot ◽  
Daniela Cortés Kretzer ◽  
Isadora Musse Nunes ◽  
Marcelo Zubaran Goldani ◽  
Juliana Rombaldi Bernardi ◽  
...  
Keyword(s):  
Weight Gain ◽  
Birth Weight ◽  
Pregnant Women ◽  
Gestational Weight Gain ◽  
Intrauterine Growth Restriction ◽  
Growth Restriction ◽  
Intrauterine Growth ◽  
Gestational Weight ◽  
Clinical Conditions ◽  
And Control

Abstract BACKGROUND: This study evaluate the influence of weight gain of pregnant women under different clinical conditions (Tobacco, Diabetes mellitus (DM), Hypertension, Intrauterine growth restriction (IUGR) and Control) on the birth weight of newborns. METHODS: This is an observational, longitudinal study nested in a prospective controlled cohort and conducted from 2011 to 2016 in three hospitals in the city of Porto Alegre (Brazil). Sociodemographic, prenatal (maternal gestational weight gain, among others) and perinatal (birth weight) data from 372 mother-child pairs were analyzed. Pearson's correlation was used to verify the relationship between gestational weight gain and birth weight. Multivariate regression was performed to determine the association between maternal weight gain in the presence of various health conditions and birth weight. RESULTS: There were no statistical differences in gestational weight gain in different health condition groups (p=0.092). However, women in the Hypertension group had a tendency to gain more weight (p = 0.097). Mothers in the intrauterine growth restriction group gained less weight. A positive correlation was observed between gestational weight gain and birth weight in the Tobacco (p = 0.003) and Control (p =0.001) groups, which remained positive only in the Control group after adjustment (p<0.004). CONCLUSIONS: Only weight gain in pregnant women without clinical changes during pregnancy seemed to influence the weight of the newborn. It is assumed that other factors, such as metabolic or nutritional, present among smoking, diabetes mellitus, hypertensive or with intrauterine growth restriction pregnant women have different modulations on the intrauterine environment and, therefore, exert a different influence on fetal growth.

scholarly journals Pathophysiological changes of umbilical vessels in intrauterine growth restriction

2014 ◽  
Vol 155 (50) ◽  
pp. 1989-1995
Author(s):  
Mária Jakó ◽  
Andrea Surányi ◽  
László Kaiser ◽  
Dóra Domokos ◽  
Róbert Gáspár ◽  
...  
Keyword(s):  
Umbilical Cord ◽  
Intrauterine Growth Restriction ◽  
Growth Restriction ◽  
Perinatal Morbidity ◽  
Control Groups ◽  
Umbilical Vessels ◽  
Intrauterine Growth ◽  
Basal Tone ◽  
Vasopressin Receptors ◽  
And Control

Introduction: The prevalence of intrauterine growth restriction is 4–5000/100,000 births, and they give the majority of perinatal morbidity. Aim: The aim of the authors was to compare the pathomorphologic data and vasoreactivity of umbilical vessels and placenta of small for date newborns to that of the normal pregnancies. Method: Samples of the umbilical cord and placenta were divided into case and control groups. Two 10 cm long segments were cut of the umbilical cord at placental insertion. Tissue bath experiment was performed on umbilical vessels and pathomorphologic data were collected according to the Royal College of Pathologists’ protocol. Results: After the development of basal tone, oxytocin and desmopressin did not enhance the vascular contraction, but the pathomorphological and ultrasonographic data were significantly different in the two groups. Conclusions: The results indicate that umbilical vessels might not have oxytocin or vasopressin receptors. The pathomorphologic and flowmetric differences could be the causes of small birth weight. Orv. Hetil., 2014, 155(50), 1989–1995.

Depression of ventilatory responses after daily, cyclic hypercapnic hypoxia in piglets

2001 ◽  
Vol 90 (3) ◽  
pp. 1065-1073 ◽  
Author(s):  
Karen A. Waters ◽  
Kellie D. Tinworth
Keyword(s):  
Minute Ventilation ◽  
Stimulus Presentation ◽  
Face Mask ◽  
Respiratory Pattern ◽  
Treatment Groups ◽  
Time To Peak ◽  
Ventilatory Responses ◽  
Arterial Blood ◽  
Hypercapnic Hypoxia ◽  
And Control

Ventilatory responses (VRs) were measured via a sealed face mask and pneumotachograph in 30 unsedated, mixed-breed miniature piglets at 12.6 ± 2.3 days of age ( day 1) and then repeated after seven daily 24-min exposures to 10% O2-6% CO2 [hypercapnic hypoxia (HH)]. Arterial blood was sampled at baseline, after 10 min of exposure, and after 10 min of recovery. VRs included hypoxia (10% O2 in N2), hypercapnia (6% CO2 in air), and HH (10% O2-6% CO2-balance N2). Treatment groups ( n = 10 each) were exposed to 24 min of HH from day 2 to 8 as sustained HH (24 min of HH and then 24 min of air) or cyclic HH (4 min of HH alternating with 4 min of air). Day 1 and 9data were compared in treatment and control groups. After cyclic HH, respiratory responses to CO2 were reduced during hypercapnia and during HH ( P < 0.001 vs. control for minute ventilation in both). In both treatment groups, time to peak minute ventilation was delayed in hypoxia ( P = 0.02, ANOVA), and response amplitude was increased ( P < 0.001 and P = 0.003, sustained and cyclic HH, respectively, vs. control). Respiratory pattern was also altered during the VRs and among treatment groups. Stimulus presentation characteristics exert effects on VRs that are independent of those elicited by daily HH.

Intrauterine growth restriction in Guinea pig impairs umbilical and systemic vascular function

Placenta ◽  
2015 ◽  
Vol 36 (4) ◽  
pp. 485-486
Author(s):  
Emilio A. Herrera ◽  
Daniela Schneider ◽  
René Alegría ◽  
Esteban Figueroa ◽  
Cristián Villanueva ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Intrauterine Growth Restriction ◽  
Vascular Function ◽  
Growth Restriction ◽  
Intrauterine Growth

scholarly journals Household air pollution, ultrasound measurement, fetal biometric parameters and intrauterine growth restriction

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Anindita Dutta ◽  
Donee Alexander ◽  
Theodore Karrison ◽  
Oludare Morhasson-Bello ◽  
Nathaniel Wilson ◽  
...  
Keyword(s):  
Air Pollution ◽  
Fetal Growth ◽  
Intrauterine Growth Restriction ◽  
Growth Restriction ◽  
Growth Trajectories ◽  
Second Trimester ◽  
Control Groups ◽  
Intrauterine Growth ◽  
Biometric Parameters ◽  
And Control

Abstract Background Low birthweight, intrauterine growth restriction (IUGR) and perinatal mortality have been associated with air pollution. However, intervention studies that use ultrasound measurements to assess the effects of household air pollution (HAP) on fetal biometric parameters (FBP) are rare. We investigated the effect of a cookstove intervention on FBP and IUGR in a randomized controlled trial (RCT) cohort of HAP-exposed pregnant Nigerian women. Methods We recruited 324 women early in the second trimester of pregnancy. Between 16 and 18 weeks, we randomized them to either continue cooking with firewood/kerosene (control group) or receive a CleanCook stove and ethanol fuel (intervention group). We measured fetal biparietal diameter (BPD), head circumference (HC), femur length (FL), abdominal circumference (AC) and ultrasound-estimated fetal weight (U-EFW) in the second and third trimesters. The women were clinically followed up at six regular time points during their pregnancies. Once during the women’s second trimester and once during the third, we made 72-h continuous measurements of their personal exposures to particulate matter having aerodynamic diameter < 2.5 μm (PM2.5). We adopted a modified intent-to-treat approach for the analysis. Differences between the intervention and control groups on impact of HAP on fetal growth trajectories were analyzed using mixed effects regression models. Results There were no significant differences in fetal growth trajectories between the intervention and control groups. Conclusions Larger studies in a setting of low ambient air pollution are required to further investigate the effect of transitioning to a cleaner fuel such as ethanol on intrauterine growth. Trial registration ClinicalTrials.gov NCT02394574; September 2012

Effects of changes in level and pattern of breathing on the sensation of dyspnea

1990 ◽  
Vol 69 (4) ◽  
pp. 1290-1295 ◽  
Author(s):  
T. Chonan ◽  
M. B. Mulholland ◽  
M. D. Altose ◽  
N. S. Cherniack
Keyword(s):  
Steady State ◽  
Spontaneous Breathing ◽  
Minute Ventilation ◽  
Constant Level ◽  
Normal Male ◽  
Respiratory Effort ◽  
Breathing Frequency ◽  
Ventilatory Responses ◽  
End Tidal ◽  
Male Subjects

Breathing during hypercapnia is determined by reflex mechanisms but may also be influenced by respiratory sensations. The present study examined the effects of voluntary changes in level and pattern of breathing on the sensation of dyspnea at a constant level of chemical drive. Studies were carried out in 15 normal male subjects during steady-state hypercapnia at an end-tidal PCO2 of 50 Torr. The intensity of dyspnea was rated on a Borg category scale. In one experiment (n = 8), the level of ventilation was increased or decreased from the spontaneously adopted level (Vspont). In another experiment (n = 9), the minute ventilation was maintained at the level spontaneously adopted at PCO2 of 50 Torr and breathing frequency was increased or decreased from the spontaneously adopted level (fspont) with reciprocal changes in tidal volume. The intensity of dyspnea (expressed as percentage of the spontaneous breathing level) correlated with ventilation (% Vspont) negatively at levels below Vspont (r = -0.70, P less than 0.001) and positively above Vspont (r = 0.80, P less than 0.001). At a constant level of ventilation, the intensity of dyspnea correlated with breathing frequency (% fspont) negatively at levels below fspont (r = -0.69, P less than 0.001) and positively at levels above fspont (r = 0.75, P less than 0.001). These results indicate that dyspnea intensifies when the level or pattern of breathing is voluntarily changed from the spontaneously adopted level. This is consistent with the possibility that ventilatory responses to changes in chemical drive may be regulated in part to minimize the sensations of respiratory effort and discomfort.

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